Trying to track down some "Jones" your help would be appreciated

Trying to track down some "Jones" your help would be appreciated

Long time ago (1950's) my mom wrote to a fellow by the name of Terry Jones who's the son of Rita Jones, After many years of correspondence she lost touch with Terry and would like to know what happened to him. In his correspondence he had mentioned that was born in South Wales. I assume that a birth certificate still exist in archival records. At this time I'll put it a posting on each of the counties of south wale in the hopes that he is still living there or has family there. There's also a possibility that he is now living in England. I am not familiar with archival record in the UK, So if anyone could point me to where I can look up his birth certificate or access census records for the area it would be a good starting point to pursue my research.